LT-1 hard start when "warm"/runs rough
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Joined: Apr 2003
Posts: 60
Likes: 0
From: Cedar Park TX
LT-1 hard start when "warm"/runs rough
Hello all. I looked and didn't see this problem, other than a guy who looked like he had a weak battery. Mine's fine.
The LT-1 has two problems. This one is where first thing in the AM, starts fairly easily. After it has been running, and maybe up to 15 minutes after run, starts real fast. But longer and up to a few hours later real hard to start. Crank and cranks and eventually catches, runs crappy for a bit (real rich, I guess) and eventually is "normal"
Now "normal" is this: half the time real smooth. Half the time rough. Can't correlate this to any exterior condition. I smooth it out when it is acting up by turning a/c on, and it idles up a bit.
I've changed opti, plugs, wires, and no difference.
EGR? If not the valve, the system? I've put the diacom on it a few times, but nothing jumps out as wrong. Right now at 123,000 miles, but it was doing the same at 43,000 miles...except the hard start part.
Any ideas?
The LT-1 has two problems. This one is where first thing in the AM, starts fairly easily. After it has been running, and maybe up to 15 minutes after run, starts real fast. But longer and up to a few hours later real hard to start. Crank and cranks and eventually catches, runs crappy for a bit (real rich, I guess) and eventually is "normal"
Now "normal" is this: half the time real smooth. Half the time rough. Can't correlate this to any exterior condition. I smooth it out when it is acting up by turning a/c on, and it idles up a bit.
I've changed opti, plugs, wires, and no difference.
EGR? If not the valve, the system? I've put the diacom on it a few times, but nothing jumps out as wrong. Right now at 123,000 miles, but it was doing the same at 43,000 miles...except the hard start part.
Any ideas?
Racer
Joined: Jan 2004
Posts: 286
Likes: 1
From: Madison WI
I had the hard starting problem when warm as well. I had a 90 with the multec injectors. When it was cold it started and ran fine, when it was warm and I shut it off for 15 minutes or more it would be difficult to start again. I changed the injectors and it worked great. At least one of the old injectors was leaking and flooding the car as it sat. I would lose fuel pressure in about 15 minutes of it sitting. I would get a guage hooked up and see how long it takes for it to leak down and lose pressure. It could be the pressure regulator making it lose pressure as well, but that shouldn't flood the engine as it sits.
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